Organic light-emitting diode (OLED) display products have been widely used in everyday life. The active-matrix organic light-emitting diode (AMOLED) display technologies enable OLED display products with lower costs, lower power consumptions, and larger sizes. In existing AMOLED technologies, there are several ways to form and pattern the organic layers. For example, the organic layers are often formed by vacuum evaporation. Shadow masks, i.e., fine metal masks (FMMs), are often used for forming or patterning subpixels or pixels. Subpixels of red (R), green (G), and blue (B) colors can be formed in certain arrangements, e.g., RGB side by side, so that a pixel in a display panel may display a full range of colors.
However, because of the demand for higher resolution, pixels or subpixels with smaller sizes are preferred in display panels, and problems in existing FMM technology may become prominent. For example, FMMs may be difficult to manufacture for smaller aperture widths. It may also be inconvenient to clean the FMMs. Additionally, in a deposition process, it may be difficult to align FMMs, and the FMMs may expand at high temperatures and/or low vacuum. These problems may cause color mixing between different pixels or subpixels in the display panel and the resolution of the display panel may be adversely affected.
Efforts have been made to improve the problems in current FMM technology. For example, microcavities may be formed between electrodes to define smaller pixels or subpixels in the AMOLED array substrate. In such array substrate, the indium tin oxide (ITO) electrode corresponding to each microcavity may be hard to etch to a desired thickness or the etching may be hard to control. As a result, cavity lengths of the microcavities may vary from design and the fabrication of the AMOLED array substrate may be difficult.